Forward and Backward Switching of Nonlinear Unidirectional Emission from GaAs Nanoantennas

Abstract

High-index III–V semiconductor nanoantennas have gained great attention for enhanced nonlinear light–matter interactions, in the past few years. However, the complexity of nonlinear emission profiles imposes severe constraints on practical applications, such as in optical communications and integrated optoelectronic devices. These complexities include the lack of unidirectional nonlinear emission and the severe challenges in switching between forward and backward emissions, due to the structure of the susceptibility tensor of the III–V nanoantennas. Here, we propose a solution to both issues via engineering the nonlinear tensor of the nanoantennas. The special nonlinear tensorial properties of zinc-blende material can be used to engineer the nonlinear characteristics via growing the nanoantennas along different crystalline orientations. Based on the nonlinear multipolar effect, we have designed and fabricated (110)-grown GaAs nanoantennas, with engineered tensorial properties, embedded in a transparent low-index material. Our technique provides an approach not only for unidirectional second-harmonic generation (SHG) forward or backward emission but also for switching from one to another. Importantly, switching the SHG emission directionality is obtained only by rotating the polarization of the incident light, without the need for physical variation of the antennas or the environment. This characteristic is an advantage, as compared to other nonlinear nanoantennas, including (100)- and (111)-grown III–V counterparts or silicon and germanium nanoantennas. Indeed, (110)-GaAs nanoantennas allow for engineering the nonlinear nanophotonic systems including nonlinear “Huygens metasurfaces” and offer exciting opportunities for various nonlinear nanophotonics technologies, such as nanoscale light routing and light sources, as well as multifunctional flat optical elements.

Nanoantenna‐Enhanced Light‐Emitting Diodes: Fundamental and Recent Progress

“…For instance, Yagi–Uda structure made of hafnium dioxide (Figure 5c) and (110)‐grown GaAs embedded in the transparent materials shows excellent performance for unidirectional second harmonic generation with polarization control. [ 87,93 ] Kuo's group achieved functional regulation by preparing SiO 2 /GaN nanoantenna arrays at specified locations on the active layer of the LED, as shown in Figure 5d, and greatly improved the conversion efficiency of the LED to 32.4%, which is attributed to the enhanced LEE and suppression of nonradiative energy transfer. [ 63,94,95 ]…”

Эффекты Магнитного Поля В Экситонной Генерации Оптических Гармоник

“…GaAsэто важный материал как для многочисленных техниче-ских применений, так и для фундаментальной физики. Недавние публикации свидетельствуют о новых нелинейных свойствах этого материала и структур на его основе [32][33][34].…”

Multipolar second-harmonic generation from high-Q quasi-BIC states in subwavelength resonators

“…Specifics of the radiation characteristics in each case can be explained by different parities of nonlinearly generated multipoles, so-called nonlinear multipolar interference. This represents an example where multipolar analysis has been proven to be a useful instrument for design of directional nonlinear light emission [31].…”